This invention relates to a system for measuring loads applied to a platform. The present invention comprises a load platform, a bottom plate, vertical links extending between the load platform and the bottom plate, support brackets mounted to the bottom plate, horizontal links extending between support brackets and the load platform, and a force measuring device mounted in each vertical and horizontal link. The links are arranged such that each link is a two force member that cannot support moments. The present invention provides a means for summing the loads in the vertical links, transverse links, and longitudinal links in order to calculate the total load on the platform.
1. Field of the Invention
The present invention relates to a system for measuring loads and braking forces applied to a platform, wherein the accuracy of the measurements is not adversely affected by any moments or torques resulting from the application of the load to the platform. The present invention is particularly suitable to platforms used to measure large loads and braking capability of trucks at weigh stations located along interstate highways.
2. Description of the Prior Art
Scales have been used for centuries to measure weights or loads. Weight measurement is an essential element of many commercial transactions and industrial process.
Prior art load scales or weight measuring devices are described in U.S. Pat. No. 3,667,560 to Cooke, U.S. Pat. No. 3,805,604 to Ormond, U.S. Pat. No. 3,891,041 to Hall, et al., and U.S. Pat. No. 3,967,691 to Wirth. These prior art devices do not provide the capability to measure large loads or braking forces applied to a flat horizontally oriented platform subjected to moment forces or torques.
The present invention is directed toward a system for making load measurements. The term xe2x80x9cloadxe2x80x9d, as used herein, refers to a force. The invention comprises a load platform comprising a bottom surface, and at least three corner regions.
The invention further comprises a bottom plate positioned underneath and in substantial vertical alignment with the platform. The bottom plate comprises at least three corner regions in substantial vertical alignment with the four corner regions of the platform.
The invention further comprises at least two support brackets mounted on the bottom plate and extending upward without touching the platform. Each bracket has an upper region.
The invention further comprises at least 10 spherical rod ends or pivot mechanisms. Six of the spherical rod ends are attached to a corner region of the platform and a corner region of the bottom plate, such that each spherical rod end attached to a corner of the platform is in substantial vertical alignment with a spherical rod end attached to a corner region of the bottom plate. A spherical rod end is attached to each upper region of each support bracket. At least two more spherical rod ends are attached to the bottom surface of the platform, outside any corner regions of the platform.
The invention further comprises at least three vertically oriented links. Each of these links comprises a first end attached to one of the spherical rod ends attached to a corner region of the platform, and a second end attached to one of the spherical rod ends attached to the bottom plate.
The invention further comprises at least two horizontal links. Each of the horizontal links has a first end attached to a spherical rod end attached to the bottom surface of the platform, outside a corner region of the platform. Each of the horizontal links has a second end attached to a spherical rod end attached to an upper region of the bracket, such that the horizonal link extends between the bottom surface of the platform and the upper region of two of the mounting brackets in a substantially perpendicular arrangement to the vertical links.
The invention further comprises a force measuring device mounted in each vertical link and in each horizontal link.